From a5002d53029df4d7ebaf87c821b3dc07b65e5e52 Mon Sep 17 00:00:00 2001 From: John Snow Date: Mon, 14 Dec 2015 14:55:16 -0500 Subject: [PATCH] block/qapi: allow best-effort query For more complex BDS trees that can be created under normal circumstances, we lose the ability to issue query commands because of our inability to re-construct the absolute filename. Instead, omit this field when it is a problem and present as much information as we can. This will change the expected output in iotest 110, where we will now see a json filename and the lack of an absolute filename instead of an error. Signed-off-by: John Snow Message-id: 1450122916-4706-6-git-send-email-jsnow@redhat.com Reviewed-by: Max Reitz Signed-off-by: Max Reitz --- block/qapi.c | 7 ++++--- tests/qemu-iotests/110.out | 5 ++++- 2 files changed, 8 insertions(+), 4 deletions(-) diff --git a/block/qapi.c b/block/qapi.c index 5587c6471c..fecac253de 100644 --- a/block/qapi.c +++ b/block/qapi.c @@ -245,10 +245,11 @@ void bdrv_query_image_info(BlockDriverState *bs, info->has_backing_filename = true; bdrv_get_full_backing_filename(bs, backing_filename2, PATH_MAX, &err); if (err) { - error_propagate(errp, err); - qapi_free_ImageInfo(info); + /* Can't reconstruct the full backing filename, so we must omit + * this field and apply a Best Effort to this query. */ g_free(backing_filename2); - return; + backing_filename2 = NULL; + error_free(err); } /* Always report the full_backing_filename if present, even if it's the diff --git a/tests/qemu-iotests/110.out b/tests/qemu-iotests/110.out index 0270980c26..b3584ff87f 100644 --- a/tests/qemu-iotests/110.out +++ b/tests/qemu-iotests/110.out @@ -11,7 +11,10 @@ backing file: t.IMGFMT.base (actual path: TEST_DIR/t.IMGFMT.base) === Non-reconstructable filename === -qemu-img: Cannot use relative backing file names for 'json:{"driver": "IMGFMT", "file": {"set-state.0.event": "read_aio", "image": {"driver": "file", "filename": "TEST_DIR/t.IMGFMT"}, "driver": "blkdebug", "set-state.0.new_state": 42}}' +image: json:{"driver": "IMGFMT", "file": {"set-state.0.event": "read_aio", "image": {"driver": "file", "filename": "TEST_DIR/t.IMGFMT"}, "driver": "blkdebug", "set-state.0.new_state": 42}} +file format: IMGFMT +virtual size: 64M (67108864 bytes) +backing file: t.IMGFMT.base (cannot determine actual path) === Backing name is always relative to the backed image ===